Design of Non Invasive Wireless Eeg Recording System

摘要

Bio medical signal monitoring systems have drawn great attention now a day by the results yielded from weighty advances in electronics and communications and field of information technologies. As an example EEG (electroencephalogram) is the most popular interface for measuring bio-potential in brain computer interface (BCI) systems which is a prominent topic organizing a direct communication link between human brain and a computer. We know that most BCI (brain computer interface) systems are bulky and hard wired EEG experiments which are inconvenient and troublesome for patients to follow their regular routine tasks. So, to overcome this problem we are going to develop a single channel wireless EEG (electroencephalogram) acquisition and recording system which will be more comfortable and convenient to the patients. The system consists of an EEG signal acquisition and processing units along with the wireless transmission and reception units. The former (analogue processing unit) includes electrodes, pre-amplifiers, filters and gain amplifiers while the later (digital processing unit) includes ADC (analogue to digital converter) and micro-controller which are used to convert the analogue EEG signals into digital signals and fulfill the digital filtering. The transmission and reception units include a Bluetooth communication module which sends the digital signals to the PC (personal computer) to be displayed over the GUI (graphical user interface). Thus the patient's EEG signal could be observed and stored without any bulky wired environment due to which the distortion caused by the long distance transmission could be reduced significantly. The key performances are: a) Long range communications (50 meters) b) ADC sampling rate is high (400 samples/sec) c) Low power consumption. d) Portable and e) Battery operated. Medical research applications based on wireless EEG acquisition system can be explored such as brain controlled games and diagnosis of diseases.